2009 IEEE International Ultrasonics Symposium最新文献

{"title":"Characterization of cMUT by Dynamic Holography Microscopy","authors":"N. Sénégond, D. Certon, Jean-Edouard Bernard, F. Teston","doi":"10.1109/ULTSYM.2009.5441729","DOIUrl":"https://doi.org/10.1109/ULTSYM.2009.5441729","url":null,"abstract":"The comparison of numerical simulations to real cMUT behavior is essential to assess and optimize the process. For a complete characterization multiple devices (FIB, SEM, impedancemetry, laser interferometry, ...) are needed. In this context, we propose to use a full-field measurement device, a Digital Holography Microscopy (DHM Lynceetec®), which acquires static and dynamic in-plane and out-of-plane information of membranes population in a single acquisition and then provides most of required parameters. This paper presents the principle of this device, its performances comparing to other ones and its limits.","PeriodicalId":368182,"journal":{"name":"2009 IEEE International Ultrasonics Symposium","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130201725","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Design optimization of polysilicon ultrasonic micromotor","authors":"S. Tin, S. Ardanuc, A. Lal","doi":"10.1109/ULTSYM.2009.5441971","DOIUrl":"https://doi.org/10.1109/ULTSYM.2009.5441971","url":null,"abstract":"We studied the actuation, vibration and rotation properties of acoustically-driven surface-macromahcined ultrasonic micromotors with different stator dimensions to achieve optimized performances. The motors have been operating continuously in air for over six months without any visible wear. This very long lifetime operation, indicative of motor reliability, in possible by non-contact operation, where the vibration of the stator, which is driven by a die-attached PZT plate, is acoustically coupled to the rotor without contact. The contact is due to fluidic coupling between the rotor and stator. When the resonant frequency of the ont of the sator's vibration mode is close to PZT plate's thickness mode resonance (∼4.2MHz), rotating wave is generated on the stator. The rotational threshold and maximum rotation speed of the motor varies with the size of the stator. While larger stator (820µm) has lower rotation threshold (3.5V), its maximum rotation speed (180 rpm) is significantly lower than smaller stator (740µm), whose maximum rotation speed is over 320 rpm with rotation threshold of 8.5V.","PeriodicalId":368182,"journal":{"name":"2009 IEEE International Ultrasonics Symposium","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131582811","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Shear modulus imaging by Spatially Modulated Ultrasound Radiation Force","authors":"S. McAleavey","doi":"10.1109/ULTSYM.2009.5441551","DOIUrl":"https://doi.org/10.1109/ULTSYM.2009.5441551","url":null,"abstract":"Spatially Modulated Ultrasound Radiation Force (SMURF) uses impulsive acoustic radiation force to generate a shear wave of known spatial frequency in a medium of unknown shear modulus. The velocity of the induced shear wave, and hence the shear modulus of the medium, is determined from the period of the induced shear wave. Here we present the first experimentally obtained images of shear modulus using the SMURF method. Images of spherical (shown below), conical, and step edge phantoms are presented. Agreement within 8% is found between SMURF and unconfined compression measurements of uniform phantoms. Image resolution on the order of the push beam spacing is observed. A key advantage of this method is that tracking is performed along a single a-line, avoiding correlated noise bias errors encountered in multiple-track location methods. We describe the source of this noise. Modulus estimates are obtained without extensive spatial averaging, allowing high resolution to be obtained.","PeriodicalId":368182,"journal":{"name":"2009 IEEE International Ultrasonics Symposium","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132644227","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Real-time ultrasound elastography in neurosurgery","authors":"C. Uff, Leo J Garcia, J. Fromageau, N. Dorward, J. Bamber","doi":"10.1109/ULTSYM.2009.5441629","DOIUrl":"https://doi.org/10.1109/ULTSYM.2009.5441629","url":null,"abstract":"This study furthers previous work by this group [1] on the use of ultrasound elastography intra-operatively in the brain. Real-time 2-dimensional (2D) ultrasound elastograms were acquired during neurosurgical operations for brain and spinal cord tumors, and, in select cases, approximately real-time 3-dimensional (3D) elastograms (volumes of axial strain data) were acquired in the brain. For the first time, elastograms were successfully generated in the spinal cord using vascular pulsations to generate internal strains. The results revealed strain data that correlated well with the surgeon's assessment of the stiffness of the tissues, and areas of reduction in cross-correlation coefficient and very high axial strain at tumor boundaries were found to correspond to cleavage planes. Off-line axial normal strain and axial shear strain calculation assisted in image interpretation. Benefits of this method in neurosurgery include pre-informing the surgeon as to the stiffness of the lesion and identification of dissection planes, both of which can lead to safer surgery.","PeriodicalId":368182,"journal":{"name":"2009 IEEE International Ultrasonics Symposium","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132799505","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Prostate-cancer imaging using machine-learning classifiers: Potential value for guiding biopsies, targeting therapy, and monitoring treatment","authors":"E. Feleppa, M. Rondeau, Paul Lee, C. Porter","doi":"10.1109/ULTSYM.2009.5442061","DOIUrl":"https://doi.org/10.1109/ULTSYM.2009.5442061","url":null,"abstract":"Prostate cancer (PCa) remains a major health concern in many countries. However, it cannot be imaged reliably by any commonly used imaging modality. Therefore, needle biopsies and treatments cannot be targeted to suspicious regions. Our objective is to develop and test an ultrasonic method based on spectrum analysis of radio-frequency (RF) ultrasound echo signals and on classification using current machine-learning tools for reliably imaging PCa and thereby guiding biopsies, targeting therapy, and eventually, monitoring treatment of PCa. RF data were acquired in the biopsy plane of 617 prostate biopsy cores obtained from 64 suspected prostate-cancer (PCa) patients. For each patient, clinical data such as PSA level also were recorded. A level of suspicion (LOS) was assigned based on the conventional image. Spectral computations were performed on acquired RF data in a region of interest that spatially matched the tissue-sampling location. Four non-linear classifiers were trained from these data using biopsy results as the gold standard: multi-layer-perceptron artificial neural networks (ANNs), logitboost algorithms (LBAs), support-vector machines (SVMs), and stacked, restricted Boltzmann machines (S-RBMs). Cross-validation methods were employed to obtain tissue-category scores. Areas under ROC curves (AUCs) were used to assess classifier performance in comparison with LOS-based performance. AUCs for the ANN, LBA, SVM, and RBM respectively were 0.84 ± 0.02, 0.87 ± 0.04, 0.89 ± 0.04, and 0.91 ± 0.04. In comparison, the LOS-based AUC was 0.64 ± 0.03. Tissue-type images (TTIs) based on these methods revealed cancerous foci that subsequently were identified histologically, but were undetected prior to prostatectomy pathology. The ultrasonic imaging methods described here show significant potential for achieving needed reliability. A clinically significant beneficial reduction in false-negative biopsy procedures would be possible if TTIs were used to guide biopsies. Benefits also would result from using TTIs to target focal treatment and reduce toxic side effects. Potentially, TTIs also could be used to assess tissue changes over time for active surveillance and therapy monitoring.","PeriodicalId":368182,"journal":{"name":"2009 IEEE International Ultrasonics Symposium","volume":"90 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132778952","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"CREASIMUS: a fast simulator of ultrasound image sequences using 3D tissue motion","authors":"A. Marion, J. Porée, D. Vray","doi":"10.1109/ULTSYM.2009.5441730","DOIUrl":"https://doi.org/10.1109/ULTSYM.2009.5441730","url":null,"abstract":"Ultrasound simulated data are often used for validation of processing algorithms. Simulation methods in medical ultrasound are based on an acoustical approach or a system approach. In this article, we present a simulator derived from the well-known system approach because of its low complexity. The simulator was developed using VTK and ITK libraries and computes then displays 4 images/second. Besides, it is divided into four tabs dedicated to selection of simulation parameters, visualization of RF/envelope data and save of simulated sequence. The user can define several parameters such as the emitting central frequency, the standard deviations of the PSF, the size of images or the displacement field between images.","PeriodicalId":368182,"journal":{"name":"2009 IEEE International Ultrasonics Symposium","volume":"252 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130768170","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A high performance spatio-temporal displacement smoothing method for myocardial strain imaging","authors":"Shuhui Bu, T. Shiina, M. Yamakawa","doi":"10.1109/ULTSYM.2009.5442020","DOIUrl":"https://doi.org/10.1109/ULTSYM.2009.5442020","url":null,"abstract":"Accurately assessing local myocardial strain is important for diagnosing ischemic heart diseases because decreased myocardial motion often appears in the early stage. The abnormal contraction motion can be visualized by myocardial strain images, but the strain calculation is very sensitive to noise. In our previous research, we proposed an adaptive dynamic grid interpolation (ADGI) method for overcoming the limitation of the trade-off between spatial resolution and accuracy in traditional moving-average filters. Usually, when the scanning frame-rate is high the correlation coefficient, which is calculated from ECAM, will be high. But only using two consecutive frames' phase-shift data, the displacements' dynamic range is low. Therefore, the strain calculation will be affected by the noise. In this research, we extend the proposed method with the ability to process two or more frames' data for improving the SNR of myocardial strain imaging. From the simulation results, we can conclude that our method can provide more accurate myocardial strain images. In a model with the infarcted region located around 1 to 3 o'clock, the RMS error is decreased to 16.8% without degrading spatial resolution.","PeriodicalId":368182,"journal":{"name":"2009 IEEE International Ultrasonics Symposium","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131034594","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Lateral motion estimator for measurement of artery-wall displacement","authors":"H. Hasegawa, H. Kanai","doi":"10.1109/ULTSYM.2009.5441634","DOIUrl":"https://doi.org/10.1109/ULTSYM.2009.5441634","url":null,"abstract":"Artery-wall motion due to the pulsation of the heart is often measured to evaluate mechanical properties of the arterial wall. Such motion is thought to occur only in the arterial radial direction because the main source of the motion is an increase of blood pressure. However, it has recently been reported that the artery also moves in the longitudinal direction. Therefore, a 2D motion estimator is required even when the artery is scanned in the longitudinal direction because the arterial wall moves both in the radial (axial) and longitudinal (lateral) directions. Methods based on 2D correlation of RF echoes are often used to estimate the lateral displacement together with axial displacement. However, these methods require much interpolation of the RF echo or correlation function to achieve a sufficient resolution in the estimation of displacement. To overcome this problem, Jensen et al. modulated the ultrasonic field in the lateral direction at a designed spatial frequency to utilize the lateral phase for the estimation of lateral motion. This method, namely, the lateral modulation method, generates complex signals whose phases change depending on the lateral motion. Therefore, the lateral displacement can be estimated with a good resolution without interpolation, although special beamformers are required. The present paper describes a method, which can be applied to ultrasonic echoes obtained by a conventional beamformer, to estimate lateral displacements using the phases of lateral fluctuations of ultrasonic echoes. In the proposed method, complex signals were generated by the Hilbert transform, and the phase shift was estimated by correlation-based estimators. The proposed method was validated using a cylindrical phantom mimicking an artery. The error in the lateral displacement estimated by the proposed method was 13.5% of the true displacement of 0.5 mm with a kernel size used for calculating the correlation function of 0.6 mm in the lateral direction, which was slightly smaller than the width at −20 dB of the maximum lateral ultrasonic field (about 0.8 mm).","PeriodicalId":368182,"journal":{"name":"2009 IEEE International Ultrasonics Symposium","volume":"81 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133519623","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ultra wide band resonator composed of grooved Cu-electrode on LiNbO3 and its application to tunable filter","authors":"M. Kadota, Tetsuya Kimura, Y. Ida","doi":"10.1109/ULTSYM.2009.5442043","DOIUrl":"https://doi.org/10.1109/ULTSYM.2009.5442043","url":null,"abstract":"A leaky surface acoustic wave (LSAW) on 0–15°YX-LiNbO3 has a large electro-mecahnical coupling factor, but it has a leaky component. The LSAW changes to Love wave without its leaky component, by using a high density metal electrode with a low velocity such as Au and Cu on that substrate. It was reported that a resonator composed of a Cu-electrode/15°YX-LiNbO3 had wide bandwidth of 12%. This time, in order to obtain a resonator with a wider bandwidth, authors attempted to fabricate one-port resonators composed of a grooved Cu-electrode/4°YX-LiNbO3. As the result, this resonator had a wider bandwidth of 17% of 1.3 times and higher resonant and anti-resonant frequencies of 1.3 times than the resonator composed of a conventional type of same thick Cu-electrode on 4°YX-LiNbO3 for reference. Authors proposed to apply this resonator to a tunable filter. As the result, the tunable filter having tunable range of 7% in center frequency was realized.","PeriodicalId":368182,"journal":{"name":"2009 IEEE International Ultrasonics Symposium","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132589413","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Measurement of elastic property of breast tissue for elasticity imaging","authors":"T. Matsumura, T. Umemoto, Y. Fujihara, E. Ueno, M. Yamakawa, T. Shiina, T. Mitake","doi":"10.1109/ULTSYM.2009.5442044","DOIUrl":"https://doi.org/10.1109/ULTSYM.2009.5442044","url":null,"abstract":"It is necessary to investigate detailed elastic property of human tissue as a foundation for developing objective and quantitative elasticity imaging (elastography). In this paper, we present our elasticity measurement method based on direct compression test for surgically-resected breast tissues. In addition, we discuss the feasibility of our approach to quantitative elastography by comparing the results of elastography obtained in vivo with those confirmed in direct compression test after extirpative surgery.","PeriodicalId":368182,"journal":{"name":"2009 IEEE International Ultrasonics Symposium","volume":"100 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133211625","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}